(1) Field of the Invention
The present invention relates particularly to organic coating compositions and methods for their use generally classified in Class 106, particularly in Subclasses 270, 271 and 272, Class 252, particularly in subclasses 51.5R, 70, 77, 392, 403 and Class 260, particularly subclass 45.8N, 308B, and 814.
(2) Description of the Prior Art
U.S. Pat. No. 3,434,987 and U.S. Pat. No. 3,474,060, to Dhein et al, teach the use of modified alkyd resins with melamine/formaldehyde and stoving at 150.degree. C.
U.S. Pat. No. 3,346,522, to Schustes, et al, teach that acrylic resins and sucrose form milky dispersions of good storage stability, which, with Chromate, make good varnishes.
U.S. Pat. No. 3,896,072, Turmuler et al, teach the use of various monomers which result in coatings of high performance; e.g., automobile use, etc. when stoved at 160.degree. C.
U.S. Pat. No. 2,662,865, Beauchamp, teach the use of amides and a phenol-formaldehyde resin in a two component system to produce laquers and varnishes.
Protection of metal surfaces by the use of varnish-type coatings has advantages, such as visibility of characters and illustrations below the coating surface, as well as decorative features. Historically, metal varnishes have required organic base solvents, with the attendant workers' exposure and environmental disadvantages. In addition, prior organically-based systems have been incapable of solubilizing many additives, such as chromates, nitrites, borates, molybdates, and triazoles.
The reported water-borne systems, on the other hand, have had other deficiencies. Rust and corrosion protection have been so poor that water borne types have been essentially restricted to cosmetic functions.
In contrast, the present invention, possibly through the use of co-solvents which tend to form azeotropes that enhance early water resistance during curing, provides coatings having substantial life even in corrosive environments. While not wishing to be bound to any theory or mechanism, it appears that the co-solvents tend to act as dispersing agents and additionally enhance stability of the liquid compositions at low temperatures.
In brief review, other prior U.S. patents of interest include:
U.S. Pat. No. 3,660,128 to Scheldahl, relating to inverted wax emulsion pastes for artwork;
U.S. Pat. Nos. 2,862,825 to Westlund et al, 2,943,945 to Saywell, and 3,565,843 to Kassinger, all relating to soluble oils, not to firm wax coatings;
U.S. Pat. No. 3,434,851 to Miller, relating to solvent-borne asphalt coatings;
U.S. Pat. Nos. 3,446,764 to Phillips, 3,699,065 to Clark, 4,184,991 to Scheurman III, 3,223,666 to Botton, 3,379,548 to Jen, 4,039,495 to Hunsucker, 4,051,089 to Tobias, and 4,081,411 to Hunsucker, all relating to base resin formulas, not to completed coatings;
U.S. Pat. No. 3,494,882 to Andrews, relating to high gloss emulsified polyester emulsions;
U.S. Pat. No. 4,187,204 to Howard, relating to water-borne paint containing, not over 10% water;
U.S. Pat. No. 4,225,477 to Vosishth and Wang, relating to co-solvent changes in water-borne coatings to control re-coatability (the coating's ability to form a substrate for a topcoat);
U.S. Pat. No. 4,148,948 to Williams, relating to a leveling additive for water dispersible paints; and,
U.S. Pat. No. 3,413,227 to Howard and Randell, relating to substituted benzotriazole.
Other patents considered in preparing this application are:
U.S. Pat. No. 3,081,238--Gurry, R. W. PA1 U.S. Pat. No. 2,900,262--Green, H. A. PA1 U.S. Pat. No. 2,669,862--Beauchamp, D. N. PA1 U.S. Pat. No. 3,804,920--Cunningham, A. L., et al. PA1 U.S. Pat. No. 3,814,709--Meissner, H. J., et al. PA1 U.S. Pat. No. 4,137,132--Ward, J. J. B. PA1 U.S. Pat. No. 3,720,616--Randell, D. R. PA1 U.S. Pat. No. 3,210,351--D'Alello, G. F. PA1 U.S. Pat. No. 3,597,353--Randell, D. R., et al. PA1 U.S. Pat. No. 3,972,845--Nikaido, et al. PA1 U.S. Pat. No. 3,282,744--Goldsmith, F. C. PA1 U.S. Pat. No. 4,169,741--Lampatzer, K., et al. PA1 U.S. Pat. No. 3,346,522--Shuster, L. K. PA1 U.S. Pat. No. 3,615,740--Goltz, K. PA1 U.S. Pat. No. 3,840,483--Guldenpfennig, R. PA1 U.S. Pat. No. 3,932,285--Ceprini, M. Q. PA1 U.S. Pat. No. 3,484,343--Kitamura, Y., et al. PA1 U.S. Pat. No. 3,953,344--Naruschima, U. PA1 U.S. Pat. No. 3,993,510--Bellaviu, P. N. PA1 U.S. Pat. No. 3,879,335--Storck, et al. PA1 U.S. Pat. No. 2,695,910--Asseff, P. A., et al. PA1 U.S. Pat. No. 3,565,678--Johnson, et al. PA1 U.S. Pat. No. 4,239,648--Marshall, et al. PA1 U.S. Pat. No. 4,059,452--Nishijima, et al. PA1 U.S. Pat. No. 3,653,931--Burchart, et al.
None of the above-cited patents teach combining the components of the present invention, and particularly not the addition of inhibitors, to form a water-borne permanent non-corrosive film, capable of formulation into light colors.